The present invention relates to an elevator installation, with a device for furnishing a temporary zone of protection, a method for mounting the device and a method for furnishing the temporary zone of protection, which device is preferably used for modernization of existing buildings or for new installations.
The elevator installation is installed in a shaft. It essentially consists of a car that is connected with a counterweight by way of support means. The car is moved along a substantially vertical car travel path by means of a drive that selectively acts on the support means or directly on the car or the counterweight. For protection of maintenance personnel, minimum protective spaces are provided in the end zones of the car travel path. The protective space ensures that the maintenance personnel, who stand in the protective space or on the car, are not put at risk even in the case of unexpected movements of the car. If in the case of existing buildings an elevator installation is newly fitted or the travel speed of the car is increased, in many instances an insufficient length of car travel path is available. The necessary minimum protective spaces cannot be provided.
If only an insufficient protective space is available, the car travel path is usually limited at the time of maintenance or when a person stands in the shaft or on the car so that the requisite protective space can be temporarily provided. The car travel path limited in that matter is termed a shortened shaft region.
An elevator installation is shown in the European patent document EP 1 118 574 in which a temporary protective space is ensured under the travel frame by activation of at least one braking device which is present. The activation is effected by, for example, the speed limiter.
The problem of this solution is that an activation by the speed limiter presupposes taking into consideration the positional information of the car, since the car, as long as it is not located in the critical end zones, has to continue travelling. This causes an increase in cost of the drive control. In addition, the drive control is not readily obvious and thereby makes visual checking by the maintenance expert difficult. Due to the conventionally usual method of triggering the speed limiter there is uncertainty with respect to the instant of actuation of the braking device, since the blocking distance of the speed limiter, for example cam distance and build up of frictional force at the speed limiter, can be difficult to define.